Print Ribbon Malfunction Detection System
Original Publication Date: 1983-Aug-01
Included in the Prior Art Database: 2005-Feb-07
A print ribbon break detection system incorporates an immediate print system shut-off control to prevent print system damage upon ribbon malfunction. Retry logic allows the print system to again attempt printing after print ribbon advancement in order to override the effects of local ribbon flaws. The print system 11 supplies printing currents to a print ribbon 13 through a set of electrodes on head 15. The print ribbon 13 is layered so as to include a resistive layer adjacent the head 15, a conductive layer and a thermoplastic pigmented layer which is brought into contact with a writing sheet (not shown) located opposite head 15. Electrode drivers 17 selectively apply print current to various ones of the print electrodes which inject the current into the resistive layer of ribbon 13.